Benchmark
The wooden 3 m or 5 m long measuring stick (not to be confused with the range stick , the leveling stick or the base stick ) was used in surveying technology to measure length in the field. With the advent of precise tape measures and electronic distance measuring devices , the rulers became less important.
The rulers are made of knot-free pine wood, which is very weather-resistant. They are about 5 cm wide and 3 cm thick in the middle. They taper towards the ends. The two ends are protected by chisel-shaped steel shoes. The two shoes are offset at right angles to each other. Since a pair of staffs is always used for the measurement in order to measure longer distances by placing the staffs next to one another, the staffs can be exactly butted against one another on the shoes that are standing crosswise.
The slats are alternately painted white-red or white-black in meter sections. To divide the length , nails large every meter and small nails every decimeter in between are driven in. The centimeters are estimated.
Wood is the preferred material for the battens because of its low change in length due to temperature. However, since the change in length as a function of moisture is noticeable, the battens must be well protected from moisture by painting.
In sloping terrain, distances with a horizontal staff must be measured in steps. The end of the crossbar on the valley side is plumbed with the plumb line on the ground. The second lath is then set at this base point.
literature
- Fritz Deumlich : Instrument science of surveying technology . 7th revised edition. VEB Verlag für Bauwesen, Berlin 1980.
- Otto Lueger : Otto Lueger's lexicon of all technology and its auxiliary sciences . Sixth Volume: Clutches to Friction . German publishing house, Stuttgart and Leipzig 1894.